Process of treating milk.



J. MOINTYRE. PROCESS OF TREATING MILK.

"APPLIOATION FILED OUT. 30, 1905. RENEWED OUT. 11, 1911.

2 SHEETS-SHEET 1.

1,026,756., I v Patented May 21, 1912.

' INVENTOH Jafin .3! 17145511 9 ATTORNEYS J. MOINTYRE- Y PROCESS OF TREATING MILK. 1

APPLIOATION FILED OUT. 30, 1905. ammwnn 0013.11, 1911'.

1,026,756. I Patented May 21, 1912.

2 BHEETS8EBET 2.

M ATTORNEYS nmrnn STATES PATENror roE.

- JOHN McINTYRE, or JERSEY crrY,,1\TEw JEnsEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO WATKIN M. GRIFFITH, or rnnnron'r, LONG ISLAND, NEW YORK.

masses or TREATING MILK. I

I Specification-of Letters Patent, Continuation of application Serial No. 102,031, filed June 18, 1903.

259,827. This application filed October 30, 1905, Serial N0.'285,175. Renewed October 11, .1911:

Serial No. 654,164.

' To all whom cit may concern.

. liquids and Be'it known that I, J'oHN MoInrYnE, a

citizen of the United States, and a resident City, in the county of Hudson-and .State o NewJersey, have invented a new and Improved Process of Treating Milk, of

of Jerse' which the following is .a full, clear, and exact description. This invention relates to' the extraction of the aqueous portion of milk and other ances, until dry solids are 'subst produced.

f The object of the invention is to. provide a new and improved process for treating milk, whereby the milk is concentratedand formed in one continuous operation into separate solid particles in the form of powder and granules, from which, by the addition of Water and the application of heat, milk '20 tic'ally true to the original milkincolor, solubility, natural souring and coagulating can be rec nstructed that is akin or pracbyv the rennet test.

In. order to produce the desired result, I' proceed in detail as follows: The milk to be treated and contained in an open vessel is heated, and at the same time highly heated air, under pressure, is passed through the milk under a constant mechanical agitation of the milk and the highly heated air, to divide the milk and the highly heated air to the minutest degree and cause an intercommingling of the air and milk particles, to insure a rapid evaporation of the aqueous portions'of the milk.. The highly heated air is preferably, passed into. the milk at the bottom of the open vessel in an uninterrupted jet extending the entire length of thecbottom of the vessel, and in the lower portion of the vessel is mounted a constantly revolving stirrer or agitator, arranged to stir or agitate the heated milk and the highly heated air, so that both are divided v and. their niinutest particles brought. intointimate contact with each other, for the highly heated ai'r'to carry 011 the moisture through the open top of the vesselv and therebyvinsure a rapid concentration of the milk ant a division thereof into dry, solid. andsoluble particles in the form of powder,

grams and granules which, by the addition reconstructed int/o milk akin'or practically true to the original. milkfin color, solubility, naturalsouring and coagulating by the rennet test. v I I In order to successfully produce the product described, the process is carried. on in one vessel at a single operation, under three essential conditions,

namely, that the air' et s maintained uninterruptedly from the eginning to the end of the operation, that of water, and the application of heat, can be ratelit a a elnom. Renewed May 31, 1905, Serial No.

the milk is kept above a ,temperature'of 90 F., and that dormancy of the milk'is wholly prevented, as otherwise fermentation or souring of themilk and consequent insolubility will occur.

In practice, I have obtained the desired result by employing as a heating ,medium for the milk a steam coil, immersedin the milk immediately above the'mechanical agitator or stirrer, and by introducing the air at about a temperature of 216 F., and this is maintained during about three-fifths oi 'the'whole time required for obtaining the product, and during'this firstperiod of the process the milk is concentrated to a thick milk consistency, and notwithstanding the coil, solubility of the solids of the milk is not lessened. At this period, the heating me dium (coil) is bodilyvremoved, and, the

milk is now reduced to a doughy consistency, and theair is introduced during this period, at a temperaturev of about 190 F., and the period lasts about one-fifth of the whole time of the process. From this doughy state of themilk, until the latter crumbles, the temperature of the heated air kept at 190 and the state of crumbling is reached inabout one-tenth of the time of the finished product isv obtained the heated high temperature of the introduced air and the whole process, and from this stage until air is passed into the milk product at 170 I F., and this last stageot' the process takes about one-tenth of the time of the whole process.

A moderate rise'or d'rkp in the tempera ture mentioned does not a' cot the perfectionof the concentrates of the milk, provided the hot air is of, sufiicient volume to prevent the temperature of the milkor its product fallbut the more rapid the concentration the plainly indieattd m Fig. 2.

better the product, and hence the approximate maximum temperature of the air as above given are preferred.

As previously stated, it is essential that no portion of the milk remains dormant during the last portion of the operation, and by mechanically agitating or stirring both the milk and the air dormancy of the milk is avoided and an intimate contact of the milk and air particles is obtained, and the air, at the high temperature, absorbs rapidly and carries away large amounts of the aqueous portion of the milk, without practical in-' jury to the solids in the milk, notably preventing a coagulation of the albuminous matter. At the end of the last period of the process, the heated air is shut oli and the stirrer is stopped, to allow of removing the product from the vessel, the product being now in condition for the market. If for commercial or other reasons it is desired to have the solid milk particles of a uniform size, then the product, after being removed from the vessel, may be run through a grinder.

In carrying out the process I prefer to use an apparatus such as shown in the accompanying drawings forming a part of this specification, in which-similar characters of reference indicate corresponding parts in both views. Figure lis a plan view of the apparatus, parts being shown in section; and Fig. 2 is a sectional side elevation of the same, on the line 22 of Fig. 1.

The vessel or tank A, as shown, is of rectangular shape, open at the top and having a semi-circular bottom A, provided throughout its length and preferably at the lowest portion, with an air induction port A for the introduction of heated air under pressure. In the bottom portion A of the vessel A is mounted to turn a stirrer or agitator B, driven from an engine C or other motor, and arranged to sweep with the end of its arms the inner surface of the semicircular bottom A of the vessel A, to prevent adherence of the milk to the bottom, and in order toscrape the doughy milk from the arms of the stirrer or agitator B,

scrapers or interceptor-s D are provided,

fixed in the vessel A and extending transversely between the arms of the stirrer, as

The air induction port. A connects wilu an air chan'iher E, into which opens an air supply pipe F, having branch pipes F and F, of which the branch pipe F is provided with a valve or damper F, and connects by a cross F with the discharge pipe G of a blower Gr 01' like device, for furnishing the compressed air needed in the process. The cross F is connected by apipe H, having a valve H with a heater H of any approved construction and from which leads the branch pipe F so that air forced by the blower G through the pipe G, cross F and pipe H into the heater H is heated in the latter, and passes in this heated condition through the pipe F 2 and F into the air chamber E. An air inlet pipe I, having a valve or damper I, also connects with the cross F and through this pipe the air from the compressor may be discharged when the valves H and F are closed, and the valve I is open. The valve F may be opened, so that a portion of Athe air from the blower G- passes through the pipe F, to mix with the heated air coming by the branch pipe F from the heater H, to reduce the temperature of the air passing into the air chamber E. Thus by the operator manipulating the valves II and F heated air to the desired degree may be passed into the air chamber E.

The coil J for heating the milk consists essentially of two heads J and J connected with each other by circulating pipes J and the said heads are adapted to rest on lugs or other supports A fixed in the vessel A (see Fig. 2). One of the heads, as

shown in the head J, is provided with a lengthwise partition J", to form. an inlet chamber J and an outlet chamber J, the chambers having normally closed spring pressed valves K and K, adapted to be opened by screw plugs or plungers L and L, under the control of the operator and extending through a St-cfill'l inlet pipe N. and an exhaust pipe N respectively, tothe out side, as plainly indicated in Fig. 1. The inlet pipe N connects with the exhaust steam pipe C of the engine C, or the said inlet pipe N may connectwith another source of steam supply.

The pipe C is provided with a valve C for controlling the how of the steam through the coil J, and the said pipe C is provided with a branch pipe C having a valve C for conducting the exhaust steam to the atmospherewhenever the valve. 0 is closed and the valve C is open, so that the exhaust steam, instead of passing to the coil J, passes into the air.

The pipes N and N have their terminals in one wall of the vessel A, and in order to bring the coil into proper position relative to the pipes N and N, the screw rod I screws in the opposite wall of the vessel A,

against the head J to move the coil into connecting position with the pipes N and N. Now when the coil is in this position, the operator first opens the chamber valves K and K by screwing the plungers L and L inwardly, so that when the valve is opened, steam passes through the chamber J" and its pipes into the head J and from the latter back by the pipes of the chamber l J into the latter,

to the outer air. Thus steam is circulated through the coil to heat the latter andthe :the removal of the coil J, the stirrer Bis middle with a. cable Q,

' the action of the stirrer milk in which the coil is immersed.

The coil J is connected at or near its forming part of a hoisting device (not shown), to permit of lowering the coil J into position on the supports A for connectinv with the steam sup ply, the said hoisting device also serving to bodily lift the coil J outof the milk after the latter has reached about a creamy con-' sistency, and the further services of the coil are dispensed with during the rest of the operation, as previously explained.

It is understood that immediately previous to the removal of the coil J from the vessel A, the valve C is closed and the plungers L and L are retracted, to allow the valves K and K to seat themselves by the action of their springs, so as to close the chambers J 5 and J and thereby prevent the milk from entering the coil. After; the valves K and K are closed, the screw rod P is unscrewed, to release or'unclamp the coil. J, to allowits being hoisted by the cable Q, out of'the milk and the vessel A. During kept in continuous action and heated air is uninterruptedly forced through the induction port A into the milk, it bein understood that by arranging the coil a ovethe stirrer the coil can be readily removed at the desired time, without interfering with and the compressed heated air.

The removal of the coil J at the time specified is desirable, to prevent the adherence and dormancy of the thickenin milk on the surface of the coil, as suchad ering product would sourandspoil the batch, especially as the milk is now rapidly concen trating to a doughy state. During this transition period, and to the end of the operation, the highly heated air supplies sufficient heatto the concentrating milk to keep the same above 90 F., to insure the formation of a perfect product.

In order to keep the induction port A at all times free from any particles of the milk, a wiper or valve R is provided, held on the crank arm R of a rock shaft R extending lengthwise in the air chamber El and passing through, and journalcd in the two heads thereof. On one outer end of 'the,rock shaft R is secured a handle R adapted to be taken hold of by the operator, to permit the latter to impart a rocking motion to the shaft- -R to move the wiper R up or down in the induction port A to clean the same of any solid matter that may adhere to the port. Ful'tl'iermdre, the wiper may serve as' a valve to partially close the port A whenever it is desired to increase the air. pres" sure The valve may also be used to com- 'pletely closethe port, to retain the milk product within the vessel A, in case the air is shut off from the chamber E. A strainer S is placed in the air supply pipe until the coil J is submerged, then the stirrer-or agitator B causes an intimate intermingling of the heated air and the heat-- ed milk, and no particle of the latter is allowed to remain dormant, and hence a very rapid concentration ofthe milk and the final formation thereof into solid, practically 'soluble and separated particles in the form of grains or granules and powder is the result, the entire process being carried out in'a single open vessel and at one continuous I operation.

In order to allow convenient removal of the finished product from the vessel A, the air chamber E is provided wit-h an air-tight door T which when opened, after the air blast is shut off andthe stirrer B ceases its rotation, allows the finished product to dro through. the'induction port A into the air chamber and through the open door T into a receiving receptacle, p

It will be seen that in my process, the milk is Wholly superimposed to the entering the whole process at the most efl'ective point. And, besides, it is F, to pre- H vent any lmpurities from being carried heated air and that, therefore, the heated air enters the milk during entered over the whole length of the milk and imrnediately broken and thoroughly difiused in the whole body of the milk by the smasher, and the evaporation is expedited thereby and the solubility of the prodnot improved. By entering-the air at the bottom I avoid the baking and consequent injury of the product that occurs on pipes that convey heated air to the product down-I wardly inside of the tank, or that contact with the product at all; besides, air so entered is localized and less effective in preventing fermentation and less economic in drying than by my practice of immediate mechanical subdivision and diffusion of the whole volume of the heated air withthe whole body of the milk.

From the foregoing it is evident that only a concentration tank whose contacting portion with the peripheral sweep of the stirrer is circular, and whose end or ends are also in sweeping contact with the end of the stirrer, will suliice, with the other meansv described, to prevent, as far as practicable, the dormancy in the product that would occur in any other form of tank, or dormancy of the product due to Wrong formation of the tank. For instance, a rectangular bottomed tank, employing my other means, may be used till the product has attained a creamy density, but to obtain the perfect product it must then be transferred to and finished ina circular bottomed tank employing the means described but for the reasons given. it is preferable to do the Whole operation in onetank.

In concentrating milk by my process, any temperature of the milk from 90 to 156 F. is perfectly safe till the product attains a creamydensity, then from 90 to 120 F., to the dry finish of the product.

In the application of heat and air in reducing milk by evaporation to a dry solid, I find that continuous rapid mechanical stirring and smashing of the Whole body of the milk by the mechanical stirrer presents a very large surface to the vapor absorbing air, as it is introduced to the milk in my process, to act upon, and this in a greater degree When the milk does thicken and rapid drying is most required; and when the milk has reached a doughy density, which condition maintains but a fraction of the whole time required for the process, the mechanical smasher rapidly subdivides it, incessantly exposing new surfaces to the heated vapor absorbing air-,that in my process strikes the product in its lowermost portion over the whole length of the tank, until it is crumbly dry, then smashed to granules and powder and stirred and dried by heated 'air entering the product over its whole length at the most effective point, till dry, fit for grinding; thus continuously, without cessation, producing at every stage of the process new and finely subdivided surfaces of the product for the ei'liciently diffused heated vapor absorbing air to act upon and, practically, preventing dormancy and fern'ientation of the whole product, and thereby producing a product that,vreconstructed milk therefrom is more akin to natural milk in color, rcnnettest, solubility milk as described, the entire process takes but a comparatively short time. The agitating of the milk and air by the stirrer B retard the thickening of the milk and keeps the latter lilled throughout with air cells, and hence nigh temperatures in both the air and the heating medium (steaan) in the coil can be employed without reduction of the temperature during the time the coil is immersed in the milk, and which time is about three-fifths of the whole time of the process. It is evident that the time required (say three and one-halfhours) for this stage of the process may be reduced proportionntely by increasing the volume of air and the heat employed, or in other Words, by doubling the volume of air and quantity of heat prac tically the same work can be accomplished in about half the time.

It is expressly understood that the temperature of the air directly entering into the milk Without cessation during the entire process is considerably above the temperature that coagulates albumen, andthat the steam heated coil imparts to the milk eontacting with it a temperature considerably above the temperature that coagulates albumen, but owing to the rapid change of position of the whole body of the milk, and the rapid minute subdivision of it, and the rapid minute diffusion in it of the air and heat,

by my process, these high temperatures do milk.

Although I have herein shown and described the improvement more particularly for treating milk, it is evident that other liquids and substances may be treated in the same manner with a view to produce dry solids.

The apparatus shown and described herein is not claimed in this application but forms the subject matter of the application for Letters Patent of the United States, for an apparatus for drying milk, #285,174, filed by me on October 30, 1905, and the product produced by the aforesaid method and apparatus forms the subject matter of the-application for Letters Patent of the United States, for a dry milk product, Serial No. 285, 170,filed by me on October 30, 1905.

Having thus described my invent-ion, I claim as new and desire to secure by Letters Patent:

1. The herein described process for producing solid milk in separated solid soluble particles, which consists in subjecting the milk in an open vessel to the action of a heating medium, directlyunder the level of the milk, and simultaneously passing highly heated air into the milk in an upward direction, and simultaneously agitating the heated air and the heated milk mechanically, below the heating medium, until the milkis reduced to an approximately creamy consistency, and then, without nterruption, continuing the action of the highly heated air and mechanical agil'ution on the reduced milk under exclusion of the heating medium for the milk, the temperature of the milk being kept'inexcess of 90 F. during the entire operation. 2. The herein described process for producing solid milk in separated soluble particles, which consists in subjecting the upper I portion of the milk, contained in an open vessel, to the' action of a heating medium and,simultaneously pas; ng a jet of heated agitation interruptedly, throughoutthe length of the said bottom portion, at the same time agitatingthe milk and the heated air mechanically throughout the bottom portion 'of' ',the milk, consistency, and continuing the mechanical and the introduction of the heated until the milk reaches a creamy air under exclusion of the heating medium,

the temperature of the milk being kept in excess of 90 tion.

In testimony whereof I have signed my name to this specification in the presence of two subscribing vituesses.

1 JOHN MGINTYRE. Witnesses .Tnno. G. 'HOSTER,

EVEHARD B. MA SHALL.

F. during the entire opera 1 

